sib

Từ điển Oxford Advanced Learner 8th

sib 7 [sib sibs] BrE [sɪb] NAmE [sɪb] noun (biology)
a brother or sister

Word Origin:
Old English ‘related by birth or descent’, of unknown origin. Modern senses date from the late 19th and early 20th cents.

• Từ đồng nghĩa / Synonyms:
  blood relation, blood relative, cognate, sibling